US 3745858 A
An improved wrench is provided which includes an oscillating power unit adapted to provide a torque to a socket assembly during each forward stroke and a ratchet which permits the power source to return to its initial position of the completion of each stroke without applying a reverse torque to the socket assembly. The wrench is designed to distribute the load of the power source evenly to the socket by causing each latch assembly of the ratchet to assume an equal share of the applied load.
Beschreibung (OCR-Text kann Fehler enthalten)
United States Patent Biach July 17, 1973  TORQUING DEVICE FOREIGN PATENTS OR APPLlCATlONS  Invent: mm Biach, 10 India" spring 124,821 8/1959 U.S.S.R 192/45 Road, Cranford, NJ. 07016 775,255 10 1934 France 192 45  Filed: Apr. 19, 1971 Primary Examiner-James L. Jones, Jr.  N04 135,113 Attorney-John H. Smoot Related U.S. Application Data  Continuation-impart of Ser. No. 842,926, July 18, 7] ABSTRA T 1969' An improved wrench is provided which includes an oscillating power unit adapted to provide a torque to a 81/5739 3 1: socket assembly during each forward stroke and a  "i l 57 ratchet which permits the power source to return to its e o are initial position of the completion of each stroke without V applying a reverse torque to the socket assembly. The wrench is designed to distribute the load of the power  v References C'ted source evenly to the socket by causing each latch as- UNITED STATES PATENTS sembly of the ratchet to assume an equal share of the 1,812,816 4/1931 Weaver 81/5739 applied load. 3,072,233 1/1963 Moo 192/45 3,283,867 11/1966 Rice 192 45 x 9 Clams, 6 Drawmg Flgures PAIENIEU JUL 1 1191s SHEET 1 0F 4 INVENTOR ATTO RN E PAIENIED V 71375 3. 745.858
' sum u UP a INVENTOR JOH/Y 1.. 8/467/ BY A M LDM' KQMMF ATTORNEYS CROSS REFERENCE TO OTHER APPLICATIONS The present application is a continuation-in-part of my application Ser. No. 842,926 filed on July 18, 1969, now abandoned for TORQUING DEVICE.
BACKGROUND OF THE INVENTION There are many applications in which it is desirable to exert relatively large torques on hexagon and other shaped nuts and similar threaded fasteners. Wrenches are suitable in the lower torque ranges, but when very large torques are required, it is difficult to obtain the necessary torque values by simply pulling on a conventional wrench. For this purpose, impact tools have been used, as have torque multipliers which generate the necessary torque by means of gearing and occasionally, a hydraulic cylinder has been applied to an ordinary box wrench so that the hydraulic cylinder pushes on the wrench and thus generates the necessary torque.
These prior art devices all have certain inherent objections. The impact tools, particularly in the larger sizes, generate very uncertain final torques and may be damaging to the threads of the fasteners. The multipliers, which depend on gearing, required a tremendous number of turns of the low torque input shaft to produce the relatively high torque on the output shaft and the wind-up or spring effect of the gearing sometimes absorbs a very substantial protion of the work stroke so that these devices are very cumbersome and inefficient to use. Further, the applying of a hydraulic cylinder to a conventional wrench requires that whenever a piston stroke has been completed, the operator must disconnect the wrench, retract the cylinder piston, and shift the wrench to a new grip on the nut. This, obviously, is a very awkward procedure.
Wrenches of the power type have been previously developed. Some of these wrenches have been of the ratchet class and have involved a driving unit encircling a socket member with latch elements connecting the two during each power stroke. When subjected to a torque involving much force, the ratchet fails because of the unequal load imposed on them. This is due to the fact that the driving unit encircling the socket member is subjected to such resistance under load that the unit in advance of the point of connection with the power means is placed under compression and the area of unit to the rear of the point of connection with the power means is subjected to tension. This results ib misalignment of the parts of the two series of ratchet assemblies that form the ratchet which transmits the full load to the socket member. Under such full load conditions, the coupled ratchet assemblies become damaged or fail completely. The loads contemplated to be handled by the present wrench are on the order of thousands of foot pounds.
SUMMARY OF THE INVENTION By means of the present invention, the applied load is transmitted equally to each latch assembly of the ratchet. Therefore, when the driving unit is operated the load will be equalized into each of the assemblies and thus, equally transmitted about the socket assembly. In this manner, the wrench may be used a great number of times without danger of damage to any of its parts and greater loads may be applied and transmitted.
BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:
FIG. 1 is a top plan view of a torquing device produced in accordance with the present invention;
FIG. 2 is a side elevational view partially in section taken along reference lines 2-2 of FIG. 1;
FIG. 3 is a front elevational view taken in the direction of the arrows 33 of FIG. 1;
FIG. 4 is an enlarged, fragmentary top plan view partially in section depicting the working parts of a first embodiment of the present wrench during a power stroke;
FIG. 5 is a view similar to FIG. 4 depicting the wrench during a return stroke; and,
FIG. 6 is a detailed plan view of an alternate ratchet assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is illustrated in the accompanying drawings wherein similar components bear the same reference numerals throughout the several views. Reference is now made to FIG. 1 in particular wherein the torquing device 10 is shown including a frame 12 to which a hydraulic cylinder 14 is mounted. The frame 12 comprises top and bottom plates 16 and 18 maintained in a spaced apart relationship by suitable spacing blocks 20 which, in turn, are secured in place by fasteners 22. The rear 24 of hydraulic cylinder 14 is pivotally mounted to frame 12. A piston is disposed for movement within cylinder 14 and a rod 26 extends from the forward end 28 of the cylinder.
The forward end 30 of piston rod 26 is connected through a clevis 32 (seen most clearly in FIG. 3) to the lower end of driving unit lever arm 34 which is mounted for rotation to frame 12 between plates 16 and 18. Two-way fluid lines 36 and 38 are coupled to the rear and forward portions of the cylinder and adapted to control the movement of the piston therein. In this connection, the fluid lines are controlled by suitable two-way valves which permit the flow of fluid in both directions of each line. Thus, when oil, air or other fluid is supplied in rear line 36, and fluid is withdrawn through forward line 38, the piston 26 will move forward, and when fluid is supplied in line 38, and fluid is withdrawn through line 36, the piston will retract into cylinder 14. It should be apparent that other sources than the described hydraulic cylinder may be used for powering the drive unit 34.
A generally circular opening extends through the driving unit 34 and aligned cut-outs are provided in the a top and bottom plates 16 and 18. A socket member 44 is disposed within the circular opening. Member 44 is in the form of a sleeve, the body 43 of which is circular and spaced from the driving unit opening. The socket member is held in position by snap ring 45.
As seen in FIGS. 4 and 5, the adjacent faces of the socket member and driving unit are formed with recesses. The recesses on each are generally complementary to those on the other. The recesses in the face of the socket member involve two inclined surfaces 54 and 56. The mating recesses in the driving unit are identifled by the numeral 60. Disposed within these recesses are coupling elements 58 which preferably take the form of cylindrical pins. Springs 50, disposed in suitable cavities 48 in the socket member, guided by headed pins 52, serve to urge the coupling elements outwardly into contact with the recessed surfaces of the driving unit. Each recess of the driving unit, its associated recess on the socket member and the associated coupling element defines a latch assembly 42. The combined latch assemblies 42 form the ratchet for the present wrench. In the illustrated embodiments, twelve such assemblies are provided disposed on 30 centers.
As the arm 34 of the driving unit is moved in a counter-clockwise direction, the ratchet assemblies will serve to couple the socket member to the drive unit and thereby rotate the socket member. When the arm 34 is retracted (i.e., rotated clockwise) the pins will be urged toward the innermost inclined surface 54 of the socket member thereby uncoupling the socket and drive unit so as to permit the free return of the drive unit without causing a corresponding rotation of the socket member. The forward and reverse strokes are illustrated respectively in FIGS. 4 and 5. It will be understood that if a hydraulic power drive is employed, liquid under presssure will be forced through line 36 in order to move the socket member on the power stroke. On the reverse stroke liquid is bled from the cylinder while air under pressure is forced through tube 38 to act against the opposite face of the piston and accordingly, retract the driving unit. The air is then vented on the next power stroke.
As will be obvious, in order to cause the ratcheting action, when the driving unit is rotated clockwise the sloping surface 62 associated with each recess 60 in the driving unit urges the pin into the inclined surface 54 of the socket member so that only the driving unit rotates.
In the illustrated embodiments, twelve ratchet assemblies are provided. For maximum efficiency, each ratchet pin should transmit one-twelfth of the total torque. This would occur if the applied load were equally distributed. It will be noted, however, that the center of clevis 32 is aligned with the diameter of the drive unit opening. Thus, it should be appreciated that the portion of the drive unit arm in front of this axis will be in compression while the portion of the lever arm behind this axis will be in tension during the power stroke so that the portion of the total load transmitted through each of the pins will be unequal. In accordance with the present invention, this effect is compensated for through adjustment of the dimensioning of the latch assemblies. Thus, in the primary embodiment, the area of each of the recesses on the driving unit lever arm is equal, the area of the recesses on the socket member is equal, the recesses on the socket member are equispaced, but the recesses on the lever arm are unequally spaced. That is, the spacing of the recesses in front of the axis are slightly further apart than equi-spacing while those behind the axis are slightly closer together. As the load is applied, compression and tension in the forward and rearward halves respectively of the lever arm distort the recess slightly so as to eventually end up with equal spacing and equal load distribution.
Altemately, the area of recesses 60 in the driving unit may be of progressively larger diameter going clockwise from the 12 o'clock position to the 6 o'clock position and of progressively smaller diameters of the same magnitude going clockwise from the 6 oclock position back to the 12 oclock position. In a successful embodiment of the present invention, the lever arm recesses were respectively 0.2188, 0.2192, 0.2196, 0.2200,
0.2204 and 0.2208 inch in that portion of the lever arm member adjacent the portion of the socket assembly under compression (going clockwise about the socket member from the 12 oclock position to the 6oclock position) and of progressively decreasing diameters (i.e., 0.2208 0.2188 inch) for that portion of the lever arm member adjacent the portion of the socket assembly under tension (going clockwise from the 60- clock position). The diameters of the latch assembly portions on the socket members were uniform.
As an additional alternative, and in many instances more desirable structure, the diameter of the pins may vary while the diameter of the recesses in the surface of the driving unit and socket member may be equal. This is shown in FIG. 6 in which the pins move outward instead of inward by the action of coil springs 65. As is also shown in this figure, the recesses of the socket member are equally spaced as are also the recesses in the driving unit. Also, the recesses of the driving unit are all of equal diameter as is also true of the recesses of the socket member. Under these circumstances, pins of progressively smaller diameter are disposed in the cavities defined by the aligned recesses of the driving member and socket member in front of the axis and pins of progressively larger diameter are disposed in the series of cavities in back of the axis. Accordingly, in a successful practice of the present invention, pins decreasing in diameter by 0.0002 inch were provided in the cavities between the 12 oclock position and 6 oclock position proceeding clockwise about the ratchet varying between 0.3750 and 0.3740 inch and pins progressively increasing in diameter by 0.002 inch were disposed in the cavities between the 6 o'clock and 12 oclock position proceeding clockwise about the ratchet. The pins again varying between 0.3740 and 0.3750 inch.
As should be apparent from the above, the present application presents the basic idea of dividing the load equally among the ratchet latch assemblies. A greater or lesser number of ratchet assemblies may be formed by providing suitable opposed recesses in the socket member and driving unit and an appropriate pin in the cavity formed between the mating recesses, the number of such assemblies to be determined by the load which is to be imposed.
Thus, the basic idea of the present invention of dividing the load equally among the ratchet assemblies may be accomplished in different ways. As shown, the recesses may be equally spaced in the driving unit (or socket member) but vary in diameter. Otherwise, the recesses may be equal in diameter but unequally spaced in the driving unit (or socket member). Alternatively, the recesses may be equal in diameter and equally spaced apart but the associated pins may vary in diameter. Under all designs, it is apparent that an equalizing of the load occurs with a plurality of ratchet assemblies.
Having thus described the invention, what is claimed l. A wrench comprising a socket member, a driving unit encircling the same, power means connected to said unit for oscillating the latter, a series of latch assemblies coupling said driving unit with said socket member as the former is rotated in one direction and providing lost motion between the socket. member and unit as the latter is rotated in an opposite direction, said latch assemblies comprising opposed recesses in the adjacent faces of the socket and driving unit and a series of latch elements disposed within said recesses for movement therein, the latch assemblies of the driving unit being successively of larger size when subjected to rotation by said power means with the socket member being under load will be sequentially subjected to compression and tensioning such unit and thus equalizes the load on each latch assembly.
2. A wrench as in claim 1 in which the recesses of the latch assemblies are equally spaced in both the socket member and driving unit, the diameter of the recesses in the driving unit being progressively smaller in size.
3. A wrench as defined in claim 1 in which the elements move in an inward direction as the wrench comes under load.
4. A wrench as defined in claim 1, the latch elements being pins of gradually increasing diameter in the area of compression and gradually decreasing diameter in the area of tension.
5. A wrench as defined in claim I, and springs for urging said latch elements inwardly into contact with surfaces of the recesses of said wrench socket member.
6. An improved torquing device comprising:
a frame member;
a reciprocating power source mounted on said frame member;
a lever arm also rotatably mounted on said frame and coupled to said power source surfaces of said lever arm defining a circular opening extending through the opposite end of said lever arm, and the surface of which is formed with a plurality of axially extending recesses;
a cylindrical socket member disposed within said lever circular opening and having surfaces defining a plurality of recesses positioned to generally align with said lever arm recesses;
a plurality of torque transmitting coupling elements for free movement within the recesses of the lever arm and socket member; whereby to provide a torque transmitting linkage between said lever arm and said cylindrical member and a second position wherein said linkage is interrupted;
coupling elements, said load equalizing means comprising the unequal dimensioning of at least one of said pluralities of lever arm recesses, socket member recesses, and coupling elements under noload condition whereby to compensate for the compressive and tensile loadings on opposite sides of said ratchet assembly under load conditions.
7. The invention in accordance with claim 6 wherein said torque transmitting coupling elements each comprise a cylindrical pin; each of said socket member recesses includes a first inclined surface and a second inclined surface spaced rearward of and in communication with said first surface; said means for normally urging each said elements to said first positions comprise springs biasing said elements toward said recess first surface; and said means for urging each of said elements to said second positions comprises a camming surface extending from each said lever arm recess and adapted to engage said elements and urge them to said second positions when a torque is applied to said lever arm in said opposite direction.
means for urging said element into said first position 8. The invention in accordance with claim 7 wherein said power source comprises a hydraulic cylinder and a reciprocating piston disposed for movement within said cylinder, said piston being pivotally coupled to said lever arm along an extension of a diameter of said lever arm circular opening, said lever arm transmitting a torque to said socket member when said piston is moving forwardly, and said lever arm recesses are unequally spaced apart from one another with the recesses forward of said diameter being spaced slightly greater apart than equi-spacing and the recesses rearward of said diameter being spaced slightly closer to one another than equi-spacing whereby when a torque is applied to said lever arm, the portion of said lever arm forward of said diameter will be in compression, tending to squeeze together said forward recesses into equal spaced relationship and the portion of said lever arm rearward of said diameter will be in tension, tending to separate said rearward recesses into equal spaced relationship so as to provide substantially equi-spacing between said recesses when a load is applied to said device to enable each of said torque transmitting coupling elements to carry an equal share of the load.
9. The invention in accordance with claim 8 wherein said lever arm recesses are of equal area, the socket member recesses are of equal area and the coupling elements are of equal diameter.